Disk recording apparatus and disk recording method

ABSTRACT

The disk recording apparatus and method are arranged to specify a recording address and a recording position on an optical disk with a wobble PM (phase modulation) format through the use of a wobble reproduced signal and a track reproduced signal. The recording apparatus operates to detect address information and a synchronous signal on the optical disk that correspond with the wobble reproduced signal and the track reproduced signal sent from the optical disk respectively. Then, the address information required for specifying a disk recording track and the synchronizing timing required for specifying a linking position are selected from the detected states.

BACKGROUND OF THE INVENTION

The present invention relates to a disk recording method and a diskrecording apparatus, and more particularly to the disk recording methodand apparatus which are required when information is linked or rewrittenonto an optical recording disk.

As a typical large-volume disk-type recording medium, a DVD (DigitalVersatile Disc) may be referred. Further, as an information-recordablemedium, recently, a write-once-read-many DVD-R or DVD+R and a rewritableDVD-RW or DVD+RW have been developed. These kinds of disks includewobbles formed on the side of each recording track on the disk and pits(land pre-pits) marked on the disk surface. For the purpose ofspecifying a recording position (track) on the disk, the data composedof a synchronous signal, address information and additional informationis modulated and recorded on those wobbles and pits.

As the method of modulating the synchronous signal, the addressinformation and the additional information, as disclosed inJP-A-2001-110061, a LPP (Land Pre-Pit) format and a wobble PM (PhaseModulation) may be referred. The LPP format is used for the DVD-R andDVD-RW disk and the PM format is used for the DVD+R and DVD+RW.

Herein, the PM format will be described with reference to FIGS. 2A to2C. FIGS. 2A to 2C illustrate one example of the PM format. FIG. 2Ashows the wobble PM method. FIG. 2B shows an ADIP (Address InPre-groove) word composition that is a component unit of the informationto be wobble-phase-modulated, the relation between one ECC block period,which corresponds to the data recording unit of the DVD and the numberof ADIP words included in the ECC block period, and a frame compositionwithin one sector that is a component unit of the ECC block. FIG. 2Cshows the block-by-block rewriting and linking methods, which areexecuted on the recording track.

In FIG. 2A, each wobble phase-modulated portion is inverted 180 degreesin phase. In a group of 93 wobbles, an ADIP synch that is located at thehead of the ADIP word, a bit synch that is located at the head of eachdata bit, and a data bit are separated at appearing intervals of thephase-modulated portions. Concretely, the ADIP synch appears at eachfour-wobble interval, the bit synch appears at each one-wobble interval,and a data bit appears at each two-wobble interval. O data is separatedfrom 1 data based on the difference of the appearing interval betweenthe bit synch and the data bit.

In FIG. 2B, the ADIP word is composed of 52 bits, concretely, an ADIPaddress, an AUX (Auxiliary) data, and an error-correcting code. The ADIPaddress is composed of three bytes, that is, data 0 (=0 fixed) and data1 to 23, the data 0 being matched to the head ADIP synch. The AUX datais composed of one byte, that is, data 24 to 31. The error-correctingcode is composed of data 32 to 51, that is, 2.5 bytes, and is used forcorrecting an error contained in the restored ADIP word. On the otherhand, the ECC block period, which corresponds to the disk recordingunit, is composed to have four ADIP words, for securing the reliabilityof access to a target ECC block. Then, the composition of the ECC blockwill be described. The ECC block is composed of 16 sectors, whichcorresponds to the access unit in reproduction, a synchronous signal,which corresponds to the synchronous unit to a data volume of one sectorin reproduction, and 26 frames each of which is composed of modulateddata. One frame is composed of 1488T data volume (in which T is achannel bit that is the basic unit of the recording mark length on thedisk, and T=26.16 MHz). The head frame of one sector includes a framesynchronous signal SY0 that indicates the sector head and a data portionID located thereafter, the data portion ID being used for specifying thetrack position in reproducing the data from the disk.

In FIG. 2C, the linking method is executed to add dummy data of 8Tbefore the ECC block including the recording information, start torecord the dummy data from the linking position of the previous ECCblock end 8T (that matches to the seventeenth wobble), and stop therecording at the linking position of the ECC block end 8T where therecording is to be ended (that matches to the seventeenth wobble), forexecuting the block-by-block rewrite and link recording. The linkingposition is specified by detecting the wobble-phase-modulated ADIPsynch, data bit, the ADIP address information, and so forth.

SUMMARY OF THE INVENTION

Today, various kinds of write-once-read-many and rewritable disks suchas DVD+R and DVD+RW are commercially made available. When rewriting orlinking information on these disks, it is necessary to specify thereproducing wobble position, that is, the linking position by detectingthe modulated address information for specifying a track position on thedisk and also the modulated synchronous signal.

Hence, the defects such as the dust adhering to the disk and the flaw ofthe disk may become an obstacle to detecting the modulated synchronoussignal or the like, thereby making the address detecting ratio lower andbringing about an adverse effect on specifying the accurate linkingposition. In the worst case, this results in shifting the linkingposition in recording the data.

If the data is recorded on the disk in the above described state, theinformation may be recorded on the different track from the targettrack, which may leads to breaking the recorded data. Further, since theinformation is recorded in the wrong linking position, when reproducingthe data, the ECC block data may be partially broken near the linkingposition, which may also leads to the burst error occurrence, therebypossibly making the reproduction disabled.

Under these circumstances, the disk recording apparatus is required torewrite and link the information even on the disk having the defect asspecifying the track position by detecting the address as well asspecifying the linking position with precision.

It is therefore an object of the present invention to provide the diskrecording method and the disk recording apparatus which are arranged toachieve the foregoing requirement.

According to the present invention, in carrying out the foregoingobject, the disk recording apparatus includes means for detecting afirst synchronous signal, which is modulated into a reproducing wobblesignal and indicates the head of a first data component unit, and firstaddress information contained in the data composition, means fordetecting a second synchronous signal, which is modulated into areproducing track signal and indicates the head of the second datacomponent unit, and second address information contained in the datacomposition, first means for selecting a detection timing of the firstsynchronous signal or a detection timing of the second synchronoussignal or the second address information, second means for selecting thefirst or the second detecting address, and control means for specifyinga linking position in synchronous to wobble positions on the disk basedon the selected detecting timing sent from the first selecting means andthe selected detecting address sent from the second selecting means andcontrolling recording of information onto a target recording tracksection.

Other objects, features and advantages of the invention will becomeapparent from the following description of the embodiments of theinvention taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing a disk recording apparatus accordingto a first embodiment of the present invention;

FIGS. 2A to 2C are views showing a wobble PM (phase modulation) formatcomposition;

FIG. 3 is a view showing a first recording method;

FIG. 4 is a view showing a second recording method;

FIG. 5 is a view showing a third recording method;

FIG. 6 is a flowchart showing the method of selecting any one of thefirst to the third recording methods; and

FIG. 7 is a block diagram showing a disk recording apparatus accordingto a second embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Hereafter, the present invention will be described with reference to theappended drawings. In FIG. 1, a numeral 1 denotes an optical disk with awobble PM (Phase Modulation) format. A numeral 2 denotes an optical headfor recording data on the disk. A numeral 3 denotes a laser driver forgenerating a recording pulse from the modulated data recorded on thedisk and controlling a semiconductor laser provided with the opticalhead in response to the generated pulse. A numeral 4 denotes an AFE(Analog Front End) for generating a difference signal from a photodetector and reproducing a wobble signal for a track on the optical disk1 as well as a recording mark on the track in response to the differencesignal. A numeral 5 denotes a phase modulated portion detector circuitfor detecting a wobble phase modulated portion and generating a phaseinverted period as a binary pulse of 0 and 1 based on the detectedresult. A numeral 6 denotes an ADIP synch detector circuit for measuringa pulse width, detecting an ADIP synch of a four-wobble width, a bitsynch of a one-wobble width and a data bit of a two-wobble synch basedon the measured result, and protecting an appearing period for each ADIPsynch. A numeral 7 denotes an ADIP address detector circuit forspecifying the head of an ADIP word from the detected ADIP synch,determining 0 or 1 data from the wobble position where the data bitappears, restoring a word composition based on the determined result,performing an error correction of the word composition, and thendetecting and protecting the ADIP address. A numeral 8 denotes a framesynch detector circuit for demodulating frame data as detecting a framesynchronous signal SYO included in a track reproducing signal. A numeral9 denotes a data portion ID detector circuit for detecting a framesynchronous signal SYO at the head of the sector, detecting a dataportion ID address from the demodulated data immediately after the framesynchronous signal SYO, and protecting the data portion ID address. Anumeral 10 denotes an address selector for selecting an address in eachECC block, the address being derived by excluding the lower two bitsfrom the ADIP address obtained by the ADIP address detector circuit 7,or another address in each ECC block, the address being derived byexcluding the lower four bits from the data portion ID address obtainedby the data portion ID detector circuit 9. A numeral 11 denotes a timingselector for selecting an ADIP synch timing detected and protected bythe ADIP synch detector circuit 6 or a data portion ID detecting timingdetected by the data portion ID detector circuit 9. A numeral 12 denotesa synchronization control circuit for controlling an output on or off ofthe synchronous timing for the selected output from the timing selector11. A numeral 13 denotes a recording control circuit for detecting atarget track on which the data is to be recorded from the obtained ECCaddress and the recording start and end ECC addresses, synchronizing thedetected track with the wobble positions based on the synchronizingtiming, specifying the linking position based on the synchronization,and thereby generating a recording control signal for a target recordingsection on the optical disk. A numeral 14 denotes a modulating circuitfor modulating the data to be recorded on the optical disk in each ECCblock, generating the recording data suited to the disk recording suchas modulating, framing and addition of a frame synchronous signal, andoutputting the generated data in response to the recording controlsignal.

In turn, the address detection, the timing synchronization forspecifying the linking position, and the recording control, which areexecuted in the recording apparatus shown in FIG. 1, will be exemplarilydescribed with reference to FIGS. 3, 4 and 5.

FIG. 3 shows the first recording method based on the synchronization ofthe ECC address obtained from the ADIP address with the ADIP synchdetection in the disk recording apparatus shown in FIG. 1. The firstrecording method may be applied to the recording of data onto an emptydisk and the link or rewrite of data on a recorded disk.

In FIG. 3, the PSN on the recording track indicates an area of each ECCblock. The PSN includes the corresponding data portion ID for 16sectors. The PSN IDs correspond with 030000˜F, 030010˜F, . . . ,respectively. In the ADIP address detector circuit 7, the ADIP addressis defined four sectors later than the ECC recording area. The addressselector 10 outputs the ECC address generated from the detected value ofthe ADIP address to the recording control circuit 13. The circuit 13compares the ECC block address for the recording start with the ECCblock address for the end, thereby detecting the recording sector. FIG.3 shows the detecting operation of the recording sector for therecording start ECC address 03001 and the recording end ECC address03002.

On the other hand, the ADIP synch detector circuit operates to detectthe ADIP synch at a forward position by 16 wobbles to the four-sectorarea included in the ECC recording area. In this first recording method,the timing selector 11 outputs the ADIP synch detection timing after theperiod is protected. Further, the synchronization control circuit 12outputs a synchronous timing between when the tracking on the opticaldisk 1 is started and when the tracking reaches the recording start ECCblock. Then, the recording control circuit 13 synchronizes itssynchronous timing with the recording timing counter for the purpose ofsynchronizing the timing counter with the wobble positions on the disk.The control circuit 13 further detects the recording section. If therecording timing counter value reaches the linking position shown inFIG. 2C, the control circuit 13 generates the recording control signaland then controls the output of the recording data to the modulatingcircuit 14 with the recording control signal, for controlling therecording of the data onto the optical disk 1.

FIG. 4 shows the second recording method based on the synchronization ofthe ECC address obtained from the data portion ID address with the ADIPsynch detection in the disk recording apparatus shown in FIG. 1. Thisrecording method is applied to the rewrite of data onto the recordedarea or the link of data from the last recording position.

In FIG. 4, the data portion ID detector circuit 9 detects the dataportion ID address value. In this case, as the output of the addressselector 10 selected is the ECC address generated from the detected dataportion ID address. The recording section is detected from the ECCaddress selected in the recording control circuit 13 and the ECCaddresses for the recording start and end. The data portion ID may bedetected only within the reproducing section of the recorded track. Theobtention of the ECC addresses and the synchronization of the recordingtiming counter are essentially required to be executed within thesector.

On the other hand, the synchronization of the recording timing isanalogous to that of the first recording method. That is, the recordingtiming counter is synchronized with the wobble positions on the disk onthe ADIP synch timing. Later, the same control as that of the firstrecording method is applied to the control for recording the data ontothe optical disk 1.

For the first and the second recording methods, concern may take placefor the accumulation of the positional shifts of the wobbles inrecording. Hence, in some cases, the synchronization control circuitdoes not control the output on the synchronous timing. In recording dataonto the disk, the synchronization of the recording timing counter withthe ADIP synch detection timing may be considered.

Further, the synchronous timing used for synchronizing the recordingtiming counter is not limited to only the ADIP synch. It may be thecombination of the ADIP synch with the wobble MP bit synch or thedetection timing of the data bit.

FIG. 5 shows the third recording method based on the synchronization ofthe ECC address obtained from the data portion ID address with the dataportion ID detection timing in the disk recording apparatus shown inFIG. 1. Like the second recording method, the third recording method isalso applied to the rewrite of data on the recorded area or the link ofdata from the last recording position.

Like the second recording method, the detection of the recording sectorin FIG. 5 is executed on the detected data portion ID address. On theother hand, the ID detection timing obtained from the data portion IDdetector circuit 9 is detected for 16 sectors included in the ECCrecording area. In this case, as the output of the timing selector 11,the detection end timing of the data portion ID is selected. Based onthe selected timing, the recording timing counter is synchronized.Later, the third recording method applies the same control as the firstrecording method to the control for recording the data onto the opticaldisk 1.

The detection of the data portion ID is made possible only within thereproducing sector of the track. The obtention of the ECC address, thedetection of the synchronizing timing, and the synchronization of therecording timing counter are essentially required to be executed withinthat sector.

In the third recording method, it is considered that the recordingtiming counter may be synchronized with the frame synchronous signal SY0that indicates the sector head or another frame synchronous signalincluding the SY0.

Further, the timing on which the recording timing counter issynchronized is not limited to the ID detection timing obtained from thedata portion ID detector circuit 9 or the detected synchronous signal ofthe frame with the SY0 as its start. If the wobble reproduction from thedisk is made possible, the recording timing counter may be synchronizedwobble by wobble, based on the binary reproducing wobble signals andtheir detection timings. In this case, the synchronization of the wobblepositions on the disk with the recording timing counter is made moreaccurate. This results in specifying the linking position moreaccurately.

Hereafter, the description will be oriented to an example of the methodfor selecting one of the first to the third recording methods that areexecuted in the recording apparatus shown in FIG. 1. The selectingmethod will be described with reference to the flowchart of FIG. 6.

In FIG. 6, when the tracking operation is switched on with respect tothe optical disk 1, the process is executed to carry out the wobblereproduction and the track reproduction (step 601). In a case that inthe step 601 the detection of the ADIP synch is made stable (locked) inthe ADIP synch detector circuit 6, if the address detecting state (step603) shows address detection in the ADIP address detector circuit, thefirst recording method is selected by controlling the selecting signalsof the address selector 10 and the timing selector 11 (step 606). In acase that in the step 603 the detection of the ADIP address is notcarried out or the ADIP address is not detected by restarting thetracking operation, if the address detecting state (step 604) showsaddress detection in the data portion ID detector circuit 9, the secondrecording method is selected by controlling the selecting signals of theaddress selector 10 and the timing selector 11 (step 606). In a casethat the ADIP synch is not stably detected or no ADIP synch is detectedin step 602, if, in the step 605, the detecting state of the dataportion ID address value shows address detection, or the detecting stateof the data portion ID detection timing or the frame synchronous signalshows timing detection, in the step 606, the third recording method isselected, and then the process of selecting the proper recording methodis terminated. If it is determined that in the steps 604 and 605 noaddress detection and timing detection are carried out, the process isexecuted to retry the tracking operation or treat the area as anon-recordable area (defective area). Then, the recording process of thesteps 606 to 606 is executed for another recording area on the opticaldisk 1.

As set forth above, according to the detecting states of the ECC addressand the synchronous timing used in the recording control circuit 13, apriority is given to the first to the third recording methods whenselecting one of them. In place, the disk recording apparatus maypre-select the recording method prior to selecting the trackingoperation.

FIG. 7 shows the disk recording apparatus according to the secondembodiment of the invention. This disk recording apparatus is arrangedto detect the ADIP address information and the ADIP synch timing fromthe wobble signal reproduced from the wobble PM type optical disk 1,convert them into the LPP signals according to the LPP (Land Pre-Pit)format, and control the recording operation in response to the LPPsignals generated. This is intended for arranging the disk recordingapparatus that enables to record data even on the disk with the wobblePM format by adding various circuits at the previous stage to the LPPsignal generating circuit in the recording apparatus for the opticaldisk with the LPP format.

In FIG. 7, a numeral 15 denotes an LPP signal generating circuit. Thiscircuit 15 composes LPP transfer data according to the LPP format,synchronizes the pulsewise LPP signal according to the synchronizingtiming, and output the pulsewise LPP signal. A numeral 16 denotes an LPPselector. This LPP selector selects the LPP reproducing signal or theLPP signal generated in the LPP signal generating circuit 15 if theoptical disk 1 has the LPP format. A numeral 17 denotes an LPP detectorcircuit that detects the LPP synchronous signal or the modulated addressinformation from the LPP signal outputted from the LPP selector 16. Thesame components as those of the disk recording apparatus shown in FIG. 1are not described herein.

In FIG. 7, if the optical disk 1 has the LPP format, the LPP detectorcircuit operates to detect the LPP synchronous signal, which ismodulated into the LPP reproduced signal from the optical disk 1, andthe address information. The recording control circuit 13 operates tosynchronize the LPP positions on the disk with the recording timingcounter, detect the recording sector of the target track according tothe detection timing and the address information, and generate therecording control signal for the linking position complying with theoptical disk with the LPP format.

Also in FIG. 7, if the optical disk 1 has the wobble PM format, the LPPgenerating circuit 15 operates to modulate the data including the ECCaddress from the synchronizing timing and the ECC address, which aredetected from the wobble reproduced signal or the track reproducedsignal of the optical disk 1, according to the LPP format, synchronizethe LPP signal with the synchronizing timing, and then output the LPPsignal generated. The method of selecting the synchronizing timing orthe ECC address is realized by the method described with respect to thefirst embodiment. The generated LPP signal is treated through the LPPdetector circuit 17 and the recording control circuit 13 describedabove, for recording the data onto the optical disk 1.

The present invention makes it possible to specify the recording targettrack and the linking position and realize the recording control evenfor the defective disk or the like.

It should be further understood by those skilled in the art thatalthough the foregoing description has been made on embodiments of theinvention, the invention is not limited thereto and various changes andmodifications may be made without departing from the spirit of theinvention and the scope of the appended claims.

1. A disk recording apparatus for recording data on an optical diskcomposed to have a wobble PM (Phase Modulation) format, comprising:means for detecting a first synchronous signal to be modulated into areproduced wobble signal and indicating the head of a first datacomponent unit and first address information contained in datacomposition; means for detecting a second synchronous signal to bemodulated into a reproduced track signal and indicating the head of asecond data component unit and second address information contained indata composition; first selecting means for selecting a detection timingof said first synchronous signal or a detection timing of said secondsynchronous signal or second address information; second selecting meansfor selecting said first or second detection address; and control meansfor specifying a linking position in synchronous to wobble positions onsaid disk, based on a selected detection timing sent from said firstselecting means and a selected detection address sent from saidselecting means and controlling a recording operation for a recordingtarget track section.
 2. A disk recording method for recording data onan optical disk composed to have a wobble PM (Phase Modulation) format,comprising the steps of: detecting a first synchronous signal to bemodulated into a reproduced wobble signal and indicating the head of afirst data component unit and first address information contained indata composition; detecting a second synchronous signal to be modulatedinto a reproduced track signal and indicating the head of a second datacomponent unit and second address information contained in datacomposition; selecting a detection timing of said first synchronoussignal or a detection timing of a second synchronous signal or secondaddress information; selecting said first or second detection address;and specifying a linking position in synchronous to wobble positions onsaid disk, based on said selected detection timing and said selecteddetection address, for recording data onto a recording target tracksector.
 3. A disk recording method as claimed in claim 2, wherein saidselected detection timing and said selected detection address is any oneof a first combination of said first synchronous signal and said firstaddress information, a second combination of said first synchronoussignal and said second address information, and a third combination ofthe detection timing of said second synchronous signal or said secondaddress information and said second address information, and the processis executed to specify a linking position in synchronous to wobblepositions on said disk, based on the selected one of said first, secondand third combinations and thereby control a recording operation for arecording target track sector.
 4. A disk recording method as claimed inclaim 3, wherein the selection of said first, second and thirdcombinations, said first combination is selected if said firstsynchronous signal is detected and said first address information isdetected, said second combination is selected if said first synchronoussignal is detected and only said second address information is selected,and said third combination is selected if no first synchronous signal isdetected and said second address information is detected.